Blowpipe for calcining incandescent filaments.



G. AUGER. BLOWPIPE FOR GALOINING INGANDESOENT FILM-(EN v APPLICATION FILED MAY 2, 1908. i 93?,2'2'7. Patented 00%.19,190 9.

Wiinesses A imomeam.

barre sra t.

GASTON AUGER, or PARIS, FRANCE.

:sLowrrrE son cALofmNe I-NGANDESCENT FILAMENIS.

To all whom it may concern:

' description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The invention herein described relates to improvements in the manufacture of incandescent filaments. The calcination of such filaments requires a high and constant 'temperature and necessitates the use of a special apparatus for this purpose. The electric furnace has been used for instance in order to obtain the high temperature required, however the electric are which passes between the carbon electrodes always produces carbon vapor which has a bad effect on tlte chemical constitution of the filaments. The filament was therefore placed beside the arc, its process of calcination however thus became unequal that is to say some parts of the filament underwent a further degree of calcination than others. In subsequent use the filament obtairled therefore soon became distorted. I i l v In order to avoid the disadvantagesreferred to the apparatus may be used which is shown by way of an example inthe accompanying drawings; I

In these drawings Figure 1 is a vertical section through the press showing the position of the blow pipe and burner A beneath the press. Fig. 2 1s acentral vertical section through a press, showing a special re-' movable mouth piece; and, Fig. 3 is a top plan view of the burner A.

The filament is squirted out of a suitable press and made to descend through an oxidizing flame in such a manner as to be heat ed over a considerable length whereby the calcination is effected in a progressive and regular manner.

The burner A is-so arranged as to direct its flame downward and has a blow-pipe connected thereto. The said blow-pipe or burner is formed of a hollow ring into which the mixture of' gases is passed which consists, as a ru1e,'ofoxygen and hydrogen v Specification of Letters latent. application filed May 2, 1903. Serial no. 430,507.

' in such a manner that the center of Patented Oct. 19., 19

or oxygen and suitable gaseous hydrocarbons. The said' gases emerge through small holesprovided' in the lower wall of the ring and arranged in a circleso that the jets of flame converge to the same point on the vertical axis along which the filament is caused to descend by the press. The filament is thus placed in the center of a flame which completely surrounds the same on all sides.

The burner is arranged beneath the press is beneath the orifice of the press. The plastic mass for the formation of-the filament is placed in the cylinder C and compressed by the piston P so as to be forced out at the orifice of said cylinder. This orifice may be made directly in the bottom of the cylinder or it may be made as the ring a special moutlr'piec'e B which is screwed into the bottom of the cylinder or otherwise mounted in-'a suitable manner as shown for instance in Fig. 2. This mouthpiece may readily be exchanged for another having a larger or a smaller opening so as to obtain filaments of different thickness.

During the process of calcination the filament descends without interruption owing to a suitableagglutinant being present in the plastic mass. It passes through the center of the annular burner and is then surroanded by a bundle of flam'esprojected down--- ward by said burner. This bundle of flames calcines the material progressively and its effect is extended throughout a considerable length of the filament. A uniform calcination is produced thereby and a homogeneous .product is thus obtained.

The temperature of the flame of the burner.may be varied by altering the ro-' portions of the constituent gases. If t we gases are adduced under constant pressure,

the length of the fiame and the temperature obtained will likewise be constant.

What I claim and deslre to secure by Letters Patent is:

1. The apparatus for calcining incandesc'entfilaments having in combination witha suitable press for trarsforming a plastic mass into filaments an annular burner with a conical bundle of fiamesipr'ojected downward through the center 0 which the filament to be calcined is made to pass, the said burner being arranged beneath the press.

1 4 men of two wit:

Witnesses:

Jinn Liaison, Emmi; v. HAY.

piece that can be readily exchanged so as to *ary the thickness OI the filament. 

